The invention relates to a system and method for monitoring the health of engines, and more particularly to monitoring the health of gas turbine engines and auxiliary power units (APUs) using acoustic data.
Aircraft gas turbine engine and APU diagnostic data is available from a variety of sources including on-board sensors such as accelerometers, which monitor rotating machinery and gears to determine vibration signatures related to particular types of component defects. However, many sensors such as accelerometers are intrusive and can be difficult to install or reinstall when components are replaced, cleaned or lubricated. Additionally, accelerometers respond to the combined resonances of all components including gears, shaft(s), bearings, blades, housing, and other moving components. This makes it difficult in some instances to isolate and identify certain types of component defects such as gear tooth defects.